The Boston Globe reports the lawyers believe they are missing about 400 potentially exculpatory documents detailing the calibration of the devices. The Office of Alcohol Testing handed over about 2,000 documents, most of which showed proper calibration.

The lawyers say the state withheld similar documents in a separate case this month that ultimately showed flawed results. They say the documents they are missing may also show calibration problems.

The state says it cannot comment on litigation but is cooperating with the court. Prosecutors say they have stopped using Breathalyzer evidence at trial until the issue is understood.